Insulation of slopes and openings of plastic windows from the outside: how to finish

Insulation of the slopes of plastic windows from the outside is usually done using polystyrene foam or penoplex. Another option is to fill the cavities with polyurethane foam and then install sandwich panels. A description of the main methods of thermal insulation and step-by-step installation instructions can be found in this material.

Insulation methods

To protect against cold and drafts, in most cases, heat-insulating materials are used, although plaster can also be used. The main methods are:

1. The use of polystyrene foam - the material is quite light, affordable, practically does not allow air to pass through, and therefore effectively retains heat. Available in convenient blocks that can be cut to any size. Although it fades in the sun, so it is not very durable in the case of windows.
2. The most common technology is finishing the outside of windows with polystyrene foam. The material is resistant to moisture, sun rays, temperature changes and rotting. It costs more than polystyrene foam, but it protects better from the cold and is also more durable.
3. Insulation of window openings in a simple case can be done using polyurethane foam. It simply fills all the voids in the space under the window. Apply in small portions, in several layers, so that the thickness of the insulating layer is 3-3.5 cm.
4. Insulating slopes by installing sandwich panels is a more reliable and aesthetic method, and it is suitable for both exterior and interior decoration. The panels can be installed after treatment with polyurethane foam - then the thermal insulation effect will be maximum.
5. Insulation of slopes from the outside is sometimes done with basalt wool. It not only protects from the cold, but also allows moisture to pass through well, i.e. it is a “breathable” material. However, its use is only possible with good waterproofing, because the cotton wool is quickly destroyed due to the ingress of water drops.
6. Treatment with plaster allows you to fill all the voids and form a strong frame. The material is resistant to temperature, sunlight and moisture. As a rule, the plaster is coated with paint on top. But if you insulate the windows from the outside with decorative plaster, finishing painting is not required.
7. Finally, fiberglass is sometimes used for thermal insulation. It is compact, reliably protects from frost, and is resistant to moisture and temperature changes. But installation of such material is more complex and requires certain skills.

Preparing for work

Regardless of the chosen material, for example, slopes made of penoplex or polystyrene foam, you first need to carry out preparatory work:

1. Determine the places of blowing with a lit candle (look where the flame fluctuates with the door tightly closed).
2. The surface is cleaned.
3. Seal the seams outside and inside.
4. Make sure of the quality of the sealing - otherwise, seal the cavities using polyurethane foam.

To proceed to the main stage and make slopes from polystyrene foam, the following tools are also prepared:

• hacksaw;
• construction tape;
• brushes;
• spatulas;
• a knife with a sharp blade (can be a stationery knife);
• construction level;
• perforator;
• miter box.
• mask, gloves;
• marker.

Step-by-step instruction

Insulation of window slopes is carried out in several stages:

1. The cleaned surface is treated with a prepared cement mixture to obtain a flat surface.
2. When the cement dries, measurements are taken and the material is cut into fragments of appropriate sizes.
3. Insulation of window slopes from the outside is usually made of polystyrene foam. The fragments are placed on glue (2-3 mm layer) and then reinforced with dowels.
4. Now you need to install the corners so that the surface is level.
5. On the outside, a special glue is applied to the insulator, onto which a reinforcing mesh is fixed.
6. Then the layer is leveled with putty.
7. To make polystyrene slopes look beautiful, they are painted with water-based paint or other materials are used for cladding.

Insulating slopes is not very difficult, but for this it is important to choose the right material. During installation, carefully prepare the surface, cleaning it from dirt, take measurements and fix the insulation with glue and dowels. If the installation is done well, the material will last for several years.